1. Field of the Invention
The present invention relates to a heat-curing cement composition, a method of hardening this composition, and a hardened body formed from this composition. More particularly, the present invention relates to a material in which the amount of mixing water necessary for obtaining a predetermined workability is small, for which the strength-manifesting properties under heating conditions are excellent, and which can be used for the production of cement secondary products (piles, Hume concrete pipes, panels and the like), construction materials, fiber-reinforced composite products and the like, and to a method of hardening this material and a hardened product formed therefrom.
2. Description of the Related Art
As the material for obtaining a high-strength product by mixing and molding at a normal temperature and curing at a high temperature, a composition comprising ordinary Portland cement or blended cement, a water-reducing agent and, if necessary, anhydrous gypsum, amorphous or crystalline silica and an expansive admixture is used, and no special consideration is paid to the clinker or cement used as the base.
As the means for promoting the manifestation of strength in a heat-cured product, a method in which the powder fineness of the cement is increased and a method in which a curing promoter or the like additive is added are adopted singly or in combination. But, when an ordinary cement is used, the workability of the paste, mortar or concrete after mixing is greatly reduced, and the physical properties of the hardened mortar or concrete are remarkably reduced. Therefore, the development of a cement having an excellent workability, strength-manifesting properties, and adhesiveness is urgently desired.